envsetup: do not print an error if complete fails

complete is a bashism; so it will fail on other shells. Avoid printing
an error if that is the case.

Change-Id: Id6d6311792f409cc3a697c7a2bb003863f1afe60
envsetup: drop unnecesary exports

export -f is a bashism and we don't actually need it, so lets remove it.

Change-Id: I9228cef0c4a9543b3d34fdc39a368ad0238431e2
Merge "envsetup: do not print an error if complete fails" into kk
Merge "envsetup: drop unnecesary exports" into kk